simplify: dedupe boilerplate and remove dead code across all layers

lib/api/marianumcloud/autocomplete/autocomplete_api.dart

@@ -1,4 +1,3 @@
-import 'dart:convert';
 import 'dart:io';
 
 import 'package:http/http.dart' as http;
@@ -38,9 +37,6 @@ class AutocompleteApi {
         technicalDetails: 'core/autocomplete/get: ${response.body}',
       );
     }
-    final decoded = jsonDecode(response.body) as Map<String, dynamic>;
-    return AutocompleteResponse.fromJson(
-      decoded['ocs'] as Map<String, dynamic>,
-    );
+    return AutocompleteResponse.fromJson(NextcloudOcs.decode(response.body));
   }
 }

lib/api/marianumcloud/nextcloud_ocs.dart

@@ -1,3 +1,5 @@
+import 'dart:convert';
+
 import '../../model/account_data.dart';
 import '../../model/endpoint_data.dart';
 
@@ -6,6 +8,11 @@ import '../../model/endpoint_data.dart';
 class NextcloudOcs {
   NextcloudOcs._();
 
+  /// Decodes an OCS v2 JSON envelope and returns its `ocs` object (the wrapper
+  /// every response nests its `meta`/`data` under).
+  static Map<String, dynamic> decode(String raw) =>
+      (jsonDecode(raw) as Map<String, dynamic>)['ocs'] as Map<String, dynamic>;
+
   static Map<String, String> headers() => {
     'Accept': 'application/json',
     'OCS-APIRequest': 'true',

lib/api/marianumcloud/search/search_files.dart

@@ -1,4 +1,3 @@
-import 'dart:convert';
 import 'dart:io';
 
 import 'package:http/http.dart' as http;
@@ -28,9 +27,7 @@ class SearchFiles {
         'Files search failed with ${response.statusCode}: ${response.body}',
       );
     }
-    final decoded = jsonDecode(response.body) as Map<String, dynamic>;
-    final ocs = decoded['ocs'] as Map<String, dynamic>;
-    final data = ocs['data'] as Map<String, dynamic>;
+    final data = NextcloudOcs.decode(response.body)['data'] as Map<String, dynamic>;
     return SearchFilesResponse.fromJson(data);
   }
 }

lib/api/marianumcloud/talk/chat/get_chat.dart

@@ -1,8 +1,7 @@
-import 'dart:convert';
-
 import 'package:http/http.dart' as http;
 import 'package:http/http.dart';
 
+import '../../nextcloud_ocs.dart';
 import '../talk_api.dart';
 import 'get_chat_params.dart';
 import 'get_chat_response.dart';
@@ -15,10 +14,8 @@ class GetChat extends TalkApi<GetChatResponse> {
     : super('v1/chat/$chatToken', null, getParameters: params.toJson());
 
   @override
-  GetChatResponse assemble(String raw) {
-    final decoded = jsonDecode(raw) as Map<String, dynamic>;
-    return GetChatResponse.fromJson(decoded['ocs'] as Map<String, dynamic>);
-  }
+  GetChatResponse assemble(String raw) =>
+      GetChatResponse.fromJson(NextcloudOcs.decode(raw));
 
   @override
   Future<Response> request(

lib/api/marianumcloud/talk/chat/long_poll_chat.dart

@@ -1,5 +1,4 @@
 import 'dart:async';
-import 'dart:convert';
 import 'dart:io';
 
 import 'package:http/http.dart' as http;
@@ -57,8 +56,7 @@ class LongPollChat {
     final status = response.statusCode;
     if (status == 304) return null;
     if (status >= 200 && status < 300) {
-      final decoded = jsonDecode(response.body) as Map<String, dynamic>;
-      return GetChatResponse.fromJson(decoded['ocs'] as Map<String, dynamic>)
+      return GetChatResponse.fromJson(NextcloudOcs.decode(response.body))
         ..headers = response.headers;
     }
     throw ServerException(

lib/api/marianumcloud/talk/close_poll/close_poll.dart

@@ -1,8 +1,7 @@
-import 'dart:convert';
-
 import 'package:http/http.dart' as http;
 
 import '../../../api_params.dart';
+import '../../nextcloud_ocs.dart';
 import '../get_poll/get_poll_state_response.dart';
 import '../talk_api.dart';
 
@@ -12,12 +11,8 @@ class ClosePoll extends TalkApi<GetPollStateResponse> {
     : super('v1/poll/$token/$pollId', null);
 
   @override
-  GetPollStateResponse assemble(String raw) {
-    final decoded = jsonDecode(raw) as Map<String, dynamic>;
-    return GetPollStateResponse.fromJson(
-      decoded['ocs'] as Map<String, dynamic>,
-    );
-  }
+  GetPollStateResponse assemble(String raw) =>
+      GetPollStateResponse.fromJson(NextcloudOcs.decode(raw));
 
   @override
   Future<http.Response> request(

lib/api/marianumcloud/talk/create_room/create_room.dart

@@ -1,8 +1,7 @@
-import 'dart:convert';
-
 import 'package:http/http.dart' as http;
 import 'package:http/http.dart';
 
+import '../../nextcloud_ocs.dart';
 import '../talk_api.dart';
 import 'create_room_params.dart';
 import 'create_room_response.dart';
@@ -13,10 +12,8 @@ class CreateRoom extends TalkApi<CreateRoomResponse> {
   CreateRoom(this.params) : super('v4/room', params);
 
   @override
-  CreateRoomResponse assemble(String raw) {
-    final decoded = jsonDecode(raw) as Map<String, dynamic>;
-    return CreateRoomResponse.fromJson(decoded['ocs'] as Map<String, dynamic>);
-  }
+  CreateRoomResponse assemble(String raw) =>
+      CreateRoomResponse.fromJson(NextcloudOcs.decode(raw));
 
   @override
   Future<Response>? request(

lib/api/marianumcloud/talk/get_participants/get_participants.dart

@@ -1,7 +1,6 @@
-import 'dart:convert';
-
 import 'package:http/http.dart' as http;
 
+import '../../nextcloud_ocs.dart';
 import '../talk_api.dart';
 import 'get_participants_response.dart';
 
@@ -10,12 +9,8 @@ class GetParticipants extends TalkApi<GetParticipantsResponse> {
   GetParticipants(this.token) : super('v4/room/$token/participants', null);
 
   @override
-  GetParticipantsResponse assemble(String raw) {
-    final decoded = jsonDecode(raw) as Map<String, dynamic>;
-    return GetParticipantsResponse.fromJson(
-      decoded['ocs'] as Map<String, dynamic>,
-    );
-  }
+  GetParticipantsResponse assemble(String raw) =>
+      GetParticipantsResponse.fromJson(NextcloudOcs.decode(raw));
 
   @override
   Future<http.Response> request(

lib/api/marianumcloud/talk/get_poll/get_poll_state.dart

@@ -1,7 +1,6 @@
-import 'dart:convert';
-
 import 'package:http/http.dart' as http;
 
+import '../../nextcloud_ocs.dart';
 import '../talk_api.dart';
 import 'get_poll_state_response.dart';
 
@@ -12,12 +11,8 @@ class GetPollState extends TalkApi<GetPollStateResponse> {
     : super('v1/poll/$token/$pollId', null);
 
   @override
-  GetPollStateResponse assemble(String raw) {
-    final decoded = jsonDecode(raw) as Map<String, dynamic>;
-    return GetPollStateResponse.fromJson(
-      decoded['ocs'] as Map<String, dynamic>,
-    );
-  }
+  GetPollStateResponse assemble(String raw) =>
+      GetPollStateResponse.fromJson(NextcloudOcs.decode(raw));
 
   @override
   Future<http.Response> request(

lib/api/marianumcloud/talk/get_reactions/get_reactions.dart

@@ -1,9 +1,8 @@
-import 'dart:convert';
-
 import 'package:http/http.dart' as http;
 import 'package:http/http.dart';
 
 import '../../../api_params.dart';
+import '../../nextcloud_ocs.dart';
 import '../talk_api.dart';
 import 'get_reactions_response.dart';
 
@@ -14,12 +13,8 @@ class GetReactions extends TalkApi<GetReactionsResponse> {
     : super('v1/reaction/$chatToken/$messageId', null);
 
   @override
-  GetReactionsResponse assemble(String raw) {
-    final decoded = jsonDecode(raw) as Map<String, dynamic>;
-    return GetReactionsResponse.fromJson(
-      decoded['ocs'] as Map<String, dynamic>,
-    );
-  }
+  GetReactionsResponse assemble(String raw) =>
+      GetReactionsResponse.fromJson(NextcloudOcs.decode(raw));
 
   @override
   Future<Response>? request(

lib/api/marianumcloud/talk/room/get_room.dart

@@ -1,7 +1,6 @@
-import 'dart:convert';
-
 import 'package:http/http.dart' as http;
 
+import '../../nextcloud_ocs.dart';
 import '../talk_api.dart';
 import 'get_room_params.dart';
 import 'get_room_response.dart';
@@ -11,10 +10,8 @@ class GetRoom extends TalkApi<GetRoomResponse> {
   GetRoom(this.params) : super('v4/room', null, getParameters: params.toJson());
 
   @override
-  GetRoomResponse assemble(String raw) {
-    final decoded = jsonDecode(raw) as Map<String, dynamic>;
-    return GetRoomResponse.fromJson(decoded['ocs'] as Map<String, dynamic>);
-  }
+  GetRoomResponse assemble(String raw) =>
+      GetRoomResponse.fromJson(NextcloudOcs.decode(raw));
 
   @override
   Future<http.Response> request(

lib/api/marianumcloud/talk/vote_poll/vote_poll.dart

@@ -3,6 +3,7 @@ import 'dart:convert';
 import 'package:http/http.dart' as http;
 
 import '../../../api_params.dart';
+import '../../nextcloud_ocs.dart';
 import '../get_poll/get_poll_state_response.dart';
 import '../talk_api.dart';
 import 'vote_poll_params.dart';
@@ -22,12 +23,8 @@ class VotePoll extends TalkApi<GetPollStateResponse> {
        );
 
   @override
-  GetPollStateResponse assemble(String raw) {
-    final decoded = jsonDecode(raw) as Map<String, dynamic>;
-    return GetPollStateResponse.fromJson(
-      decoded['ocs'] as Map<String, dynamic>,
-    );
-  }
+  GetPollStateResponse assemble(String raw) =>
+      GetPollStateResponse.fromJson(NextcloudOcs.decode(raw));
 
   @override
   Future<http.Response>? request(

lib/api/marianumconnect/marianumconnect_api.dart

@@ -10,11 +10,25 @@ import 'auth/auth_interceptor.dart';
 class MarianumConnectApi {
   static const Duration _connectTimeout = Duration(seconds: 10);
   static const Duration _receiveTimeout = Duration(seconds: 20);
+  static const Duration _plainReceiveTimeout = Duration(seconds: 15);
 
   static final Dio _instance = _build();
 
   static Dio dio() => _instance;
 
+  /// A fresh dio with the standard JSON options but no interceptors — used by
+  /// the auth queries (login/verify) that must bypass the bearer/demo
+  /// interceptors to avoid a re-auth loop.
+  static Dio plainDio() => Dio(
+    BaseOptions(
+      connectTimeout: _connectTimeout,
+      sendTimeout: _connectTimeout,
+      receiveTimeout: _plainReceiveTimeout,
+      responseType: ResponseType.json,
+      contentType: 'application/json',
+    ),
+  );
+
   static Dio _build() {
     final dio = Dio(
       BaseOptions(

lib/api/marianumconnect/marianumconnect_query.dart

@@ -26,4 +26,36 @@ abstract class MarianumConnectQuery {
       throw mapMarianumConnectError(e);
     }
   }
+
+  /// GETs [path] and parses the JSON object body with [fromJson].
+  Future<T> getObject<T>(
+    String path,
+    T Function(Map<String, dynamic> json) fromJson, {
+    Map<String, dynamic>? queryParameters,
+  }) => guard(() async {
+    final response = await dio.get<Map<String, dynamic>>(
+      endpoint(path),
+      queryParameters: queryParameters,
+    );
+    return fromJson(response.data!);
+  });
+
+  /// GETs [path] and maps each element of the JSON array body with [fromJson].
+  Future<List<T>> getList<T>(
+    String path,
+    T Function(Map<String, dynamic> json) fromJson, {
+    Map<String, dynamic>? queryParameters,
+  }) => guard(() async {
+    final response = await dio.get<List<dynamic>>(
+      endpoint(path),
+      queryParameters: queryParameters,
+    );
+    return response.data!
+        .map((e) => fromJson(e as Map<String, dynamic>))
+        .toList();
+  });
+
+  /// Formats [d] as an ISO `yyyy-MM-dd` day for MarianumConnect query params.
+  String isoDate(DateTime d) =>
+      '${d.year.toString().padLeft(4, '0')}-${d.month.toString().padLeft(2, '0')}-${d.day.toString().padLeft(2, '0')}';
 }

lib/api/marianumconnect/queries/auth_login/auth_login.dart

@@ -1,6 +1,7 @@
 import 'package:dio/dio.dart';
 
 import '../../auth/token_storage.dart';
+import '../../marianumconnect_api.dart';
 import '../../marianumconnect_query.dart';
 import 'auth_login_response.dart';
 
@@ -9,9 +10,6 @@ import 'auth_login_response.dart';
 /// run through the shared dio instance — that one has the interceptor, which
 /// would attempt to re-auth us into a loop if our credentials are wrong.
 class AuthLogin extends MarianumConnectQuery {
-  static const Duration _connectTimeout = Duration(seconds: 10);
-  static const Duration _receiveTimeout = Duration(seconds: 15);
-
   final MarianumConnectTokenStorage _tokenStorage;
 
   AuthLogin({
@@ -19,17 +17,7 @@ class AuthLogin extends MarianumConnectQuery {
         const MarianumConnectTokenStorage(),
     Dio? dio,
   }) : _tokenStorage = tokenStorage,
-       super(dio: dio ?? _buildDio());
-
-  static Dio _buildDio() => Dio(
-    BaseOptions(
-      connectTimeout: _connectTimeout,
-      receiveTimeout: _receiveTimeout,
-      sendTimeout: _connectTimeout,
-      responseType: ResponseType.json,
-      contentType: 'application/json',
-    ),
-  );
+       super(dio: dio ?? MarianumConnectApi.plainDio());
 
   Future<AuthLoginResponse> run({
     required String username,

lib/api/marianumconnect/queries/auth_verify/auth_verify.dart

@@ -2,6 +2,7 @@ import 'package:dio/dio.dart';
 
 import '../../../errors/auth_exception.dart';
 import '../../auth/token_storage.dart';
+import '../../marianumconnect_api.dart';
 import '../../marianumconnect_query.dart';
 
 /// Probes that the stored bearer token still maps to the given credentials.
@@ -12,9 +13,6 @@ import '../../marianumconnect_query.dart';
 /// Bypasses the shared dio singleton so the auth interceptor doesn't kick in
 /// and obscure a real 401 with a silent re-login.
 class AuthVerify extends MarianumConnectQuery {
-  static const Duration _connectTimeout = Duration(seconds: 10);
-  static const Duration _receiveTimeout = Duration(seconds: 15);
-
   final MarianumConnectTokenStorage _tokenStorage;
 
   AuthVerify({
@@ -22,17 +20,7 @@ class AuthVerify extends MarianumConnectQuery {
         const MarianumConnectTokenStorage(),
     Dio? dio,
   }) : _tokenStorage = tokenStorage,
-       super(dio: dio ?? _buildDio());
-
-  static Dio _buildDio() => Dio(
-    BaseOptions(
-      connectTimeout: _connectTimeout,
-      sendTimeout: _connectTimeout,
-      receiveTimeout: _receiveTimeout,
-      responseType: ResponseType.json,
-      contentType: 'application/json',
-    ),
-  );
+       super(dio: dio ?? MarianumConnectApi.plainDio());
 
   /// Throws [AuthException] on 401 (credentials no longer match the token's
   /// user, token missing, or token rejected), other [AppException]s on

lib/api/marianumconnect/queries/get_breakers/get_breakers.dart

@@ -7,8 +7,6 @@ import 'get_breakers_response.dart';
 class GetBreakers extends MarianumConnectQuery {
   GetBreakers({super.dio});
 
-  Future<GetBreakersResponse> run() => guard(() async {
-    final response = await dio.get<Map<String, dynamic>>(endpoint('breaker'));
-    return GetBreakersResponse.fromJson(response.data!);
-  });
+  Future<GetBreakersResponse> run() =>
+      getObject('breaker', GetBreakersResponse.fromJson);
 }

lib/api/marianumconnect/queries/get_capabilities/get_capabilities.dart

@@ -7,10 +7,6 @@ import 'get_capabilities_response.dart';
 class GetCapabilities extends MarianumConnectQuery {
   GetCapabilities({super.dio});
 
-  Future<CapabilitiesResponse> run() => guard(() async {
-    final response = await dio.get<Map<String, dynamic>>(
-      endpoint('me/capabilities'),
-    );
-    return CapabilitiesResponse.fromJson(response.data!);
-  });
+  Future<CapabilitiesResponse> run() =>
+      getObject('me/capabilities', CapabilitiesResponse.fromJson);
 }

lib/api/marianumconnect/queries/get_holidays/get_holidays.dart

@@ -4,10 +4,5 @@ import '../../models/mc_holiday.dart';
 class GetHolidays extends MarianumConnectQuery {
   GetHolidays({super.dio});
 
-  Future<List<McHoliday>> run() => guard(() async {
-    final response = await dio.get<List<dynamic>>(endpoint('holidays'));
-    return response.data!
-        .map((e) => McHoliday.fromJson(e as Map<String, dynamic>))
-        .toList();
-  });
+  Future<List<McHoliday>> run() => getList('holidays', McHoliday.fromJson);
 }

lib/api/marianumconnect/queries/get_ticker/get_ticker.dart

@@ -6,8 +6,6 @@ import 'get_ticker_response.dart';
 class GetTicker extends MarianumConnectQuery {
   GetTicker({super.dio});
 
-  Future<TickerResponse> run() => guard(() async {
-    final response = await dio.get<Map<String, dynamic>>(endpoint('ticker'));
-    return TickerResponse.fromJson(response.data!);
-  });
+  Future<TickerResponse> run() =>
+      getObject('ticker', TickerResponse.fromJson);
 }

lib/api/marianumconnect/queries/get_ticker_nav/get_ticker_nav.dart

@@ -6,10 +6,6 @@ import 'get_ticker_nav_response.dart';
 class GetTickerNav extends MarianumConnectQuery {
   GetTickerNav({super.dio});
 
-  Future<TickerNavResponse> run() => guard(() async {
-    final response = await dio.get<Map<String, dynamic>>(
-      endpoint('ticker/pages'),
-    );
-    return TickerNavResponse.fromJson(response.data!);
-  });
+  Future<TickerNavResponse> run() =>
+      getObject('ticker/pages', TickerNavResponse.fromJson);
 }

lib/api/marianumconnect/queries/timetable_custom_events/timetable_custom_events_get.dart

@@ -4,10 +4,8 @@ import '../../marianumconnect_query.dart';
 class TimetableCustomEventsGet extends MarianumConnectQuery {
   TimetableCustomEventsGet({super.dio});
 
-  Future<GetCustomTimetableEventResponse> run() => guard(() async {
-    final response = await dio.get<Map<String, dynamic>>(
-      endpoint('timetable/custom-events'),
-    );
-    return GetCustomTimetableEventResponse.fromJson(response.data!);
-  });
+  Future<GetCustomTimetableEventResponse> run() => getObject(
+    'timetable/custom-events',
+    GetCustomTimetableEventResponse.fromJson,
+  );
 }

lib/api/marianumconnect/queries/timetable_get_classes/timetable_get_classes.dart

@@ -4,13 +4,11 @@ import 'timetable_get_classes_response.dart';
 class TimetableGetClasses extends MarianumConnectQuery {
   TimetableGetClasses({super.dio});
 
-  Future<TimetableGetClassesResponse> run() => guard(() async {
-    final response = await dio.get<List<dynamic>>(
-      endpoint('timetable/elements/classes'),
-    );
-    final list = response.data!
-        .map((e) => McTimetableClass.fromJson(e as Map<String, dynamic>))
-        .toList();
-    return TimetableGetClassesResponse(result: list);
-  });
+  Future<TimetableGetClassesResponse> run() async =>
+      TimetableGetClassesResponse(
+        result: await getList(
+          'timetable/elements/classes',
+          McTimetableClass.fromJson,
+        ),
+      );
 }

lib/api/marianumconnect/queries/timetable_get_element_week/timetable_get_element_week.dart

@@ -13,14 +13,9 @@ class TimetableGetElementWeek extends MarianumConnectQuery {
     required int id,
     required DateTime from,
     required DateTime until,
-  }) => guard(() async {
-    final response = await dio.get<Map<String, dynamic>>(
-      endpoint('timetable/${type.pathSegment}/$id'),
-      queryParameters: {'from': _format(from), 'until': _format(until)},
-    );
-    return TimetableGetWeekResponse.fromJson(response.data!);
-  });
-
-  String _format(DateTime d) =>
-      '${d.year.toString().padLeft(4, '0')}-${d.month.toString().padLeft(2, '0')}-${d.day.toString().padLeft(2, '0')}';
+  }) => getObject(
+    'timetable/${type.pathSegment}/$id',
+    TimetableGetWeekResponse.fromJson,
+    queryParameters: {'from': isoDate(from), 'until': isoDate(until)},
+  );
 }

lib/api/marianumconnect/queries/timetable_get_holidays/timetable_get_holidays.dart

@@ -4,13 +4,8 @@ import 'timetable_get_holidays_response.dart';
 class TimetableGetHolidays extends MarianumConnectQuery {
   TimetableGetHolidays({super.dio});
 
-  Future<TimetableGetHolidaysResponse> run() => guard(() async {
-    final response = await dio.get<List<dynamic>>(
-      endpoint('timetable/holidays'),
-    );
-    final list = response.data!
-        .map((e) => McHoliday.fromJson(e as Map<String, dynamic>))
-        .toList();
-    return TimetableGetHolidaysResponse(result: list);
-  });
+  Future<TimetableGetHolidaysResponse> run() async =>
+      TimetableGetHolidaysResponse(
+        result: await getList('timetable/holidays', McHoliday.fromJson),
+      );
 }

lib/api/marianumconnect/queries/timetable_get_rooms/timetable_get_rooms.dart

@@ -4,11 +4,7 @@ import 'timetable_get_rooms_response.dart';
 class TimetableGetRooms extends MarianumConnectQuery {
   TimetableGetRooms({super.dio});
 
-  Future<TimetableGetRoomsResponse> run() => guard(() async {
-    final response = await dio.get<List<dynamic>>(endpoint('timetable/rooms'));
-    final list = response.data!
-        .map((e) => McRoom.fromJson(e as Map<String, dynamic>))
-        .toList();
-    return TimetableGetRoomsResponse(result: list);
-  });
+  Future<TimetableGetRoomsResponse> run() async => TimetableGetRoomsResponse(
+    result: await getList('timetable/rooms', McRoom.fromJson),
+  );
 }

lib/api/marianumconnect/queries/timetable_get_schoolyear/timetable_get_schoolyear.dart

@@ -4,10 +4,6 @@ import 'timetable_get_schoolyear_response.dart';
 class TimetableGetSchoolyear extends MarianumConnectQuery {
   TimetableGetSchoolyear({super.dio});
 
-  Future<TimetableGetSchoolyearResponse> run() => guard(() async {
-    final response = await dio.get<Map<String, dynamic>>(
-      endpoint('timetable/schoolyear'),
-    );
-    return TimetableGetSchoolyearResponse.fromJson(response.data!);
-  });
+  Future<TimetableGetSchoolyearResponse> run() =>
+      getObject('timetable/schoolyear', TimetableGetSchoolyearResponse.fromJson);
 }

lib/api/marianumconnect/queries/timetable_get_students/timetable_get_students.dart

@@ -4,13 +4,11 @@ import 'timetable_get_students_response.dart';
 class TimetableGetStudents extends MarianumConnectQuery {
   TimetableGetStudents({super.dio});
 
-  Future<TimetableGetStudentsResponse> run() => guard(() async {
-    final response = await dio.get<List<dynamic>>(
-      endpoint('timetable/elements/students'),
-    );
-    final list = response.data!
-        .map((e) => McTimetableStudent.fromJson(e as Map<String, dynamic>))
-        .toList();
-    return TimetableGetStudentsResponse(result: list);
-  });
+  Future<TimetableGetStudentsResponse> run() async =>
+      TimetableGetStudentsResponse(
+        result: await getList(
+          'timetable/elements/students',
+          McTimetableStudent.fromJson,
+        ),
+      );
 }

lib/api/marianumconnect/queries/timetable_get_subjects/timetable_get_subjects.dart

@@ -4,13 +4,8 @@ import 'timetable_get_subjects_response.dart';
 class TimetableGetSubjects extends MarianumConnectQuery {
   TimetableGetSubjects({super.dio});
 
-  Future<TimetableGetSubjectsResponse> run() => guard(() async {
-    final response = await dio.get<List<dynamic>>(
-      endpoint('timetable/subjects'),
-    );
-    final list = response.data!
-        .map((e) => McSubject.fromJson(e as Map<String, dynamic>))
-        .toList();
-    return TimetableGetSubjectsResponse(result: list);
-  });
+  Future<TimetableGetSubjectsResponse> run() async =>
+      TimetableGetSubjectsResponse(
+        result: await getList('timetable/subjects', McSubject.fromJson),
+      );
 }

lib/api/marianumconnect/queries/timetable_get_teachers/timetable_get_teachers.dart

@@ -4,13 +4,11 @@ import 'timetable_get_teachers_response.dart';
 class TimetableGetTeachers extends MarianumConnectQuery {
   TimetableGetTeachers({super.dio});
 
-  Future<TimetableGetTeachersResponse> run() => guard(() async {
-    final response = await dio.get<List<dynamic>>(
-      endpoint('timetable/elements/teachers'),
-    );
-    final list = response.data!
-        .map((e) => McTimetableTeacherElement.fromJson(e as Map<String, dynamic>))
-        .toList();
-    return TimetableGetTeachersResponse(result: list);
-  });
+  Future<TimetableGetTeachersResponse> run() async =>
+      TimetableGetTeachersResponse(
+        result: await getList(
+          'timetable/elements/teachers',
+          McTimetableTeacherElement.fromJson,
+        ),
+      );
 }

lib/api/marianumconnect/queries/timetable_get_timegrid/timetable_get_timegrid.dart

@@ -4,13 +4,8 @@ import 'timetable_get_timegrid_response.dart';
 class TimetableGetTimegrid extends MarianumConnectQuery {
   TimetableGetTimegrid({super.dio});
 
-  Future<TimetableGetTimegridResponse> run() => guard(() async {
-    final response = await dio.get<List<dynamic>>(
-      endpoint('timetable/timegrid'),
-    );
-    final list = response.data!
-        .map((e) => McTimegridUnit.fromJson(e as Map<String, dynamic>))
-        .toList();
-    return TimetableGetTimegridResponse(result: list);
-  });
+  Future<TimetableGetTimegridResponse> run() async =>
+      TimetableGetTimegridResponse(
+        result: await getList('timetable/timegrid', McTimegridUnit.fromJson),
+      );
 }

lib/api/marianumconnect/queries/timetable_get_week/timetable_get_week.dart

@@ -7,14 +7,9 @@ class TimetableGetWeek extends MarianumConnectQuery {
   Future<TimetableGetWeekResponse> run({
     required DateTime from,
     required DateTime until,
-  }) => guard(() async {
-    final response = await dio.get<Map<String, dynamic>>(
-      endpoint('timetable/me'),
-      queryParameters: {'from': _format(from), 'until': _format(until)},
-    );
-    return TimetableGetWeekResponse.fromJson(response.data!);
-  });
-
-  String _format(DateTime d) =>
-      '${d.year.toString().padLeft(4, '0')}-${d.month.toString().padLeft(2, '0')}-${d.day.toString().padLeft(2, '0')}';
+  }) => getObject(
+    'timetable/me',
+    TimetableGetWeekResponse.fromJson,
+    queryParameters: {'from': isoDate(from), 'until': isoDate(until)},
+  );
 }

lib/api/marianumconnect/queries/user_search/user_search.dart

@@ -7,14 +7,11 @@ import 'user_search_response.dart';
 class UserSearch extends MarianumConnectQuery {
   UserSearch({super.dio});
 
-  Future<UserSearchResponse> run(String query) => guard(() async {
-    final response = await dio.get<List<dynamic>>(
-      endpoint('users/search'),
+  Future<UserSearchResponse> run(String query) async => UserSearchResponse(
+    result: await getList(
+      'users/search',
+      McUserSearchResult.fromJson,
       queryParameters: {'q': query},
-    );
-    final list = response.data!
-        .map((e) => McUserSearchResult.fromJson(e as Map<String, dynamic>))
-        .toList();
-    return UserSearchResponse(result: list);
-  });
+    ),
+  );
 }

lib/extensions/date_time.dart

@@ -13,12 +13,8 @@ extension IsSameDay on DateTime {
 
   TimeOfDay toTimeOfDay() => TimeOfDay(hour: hour, minute: minute);
 
-  bool isSameDateTime(DateTime other) {
-    var isSameDay = this.isSameDay(other);
-    var isSameTimeOfDay = (toTimeOfDay() == other.toTimeOfDay());
-
-    return isSameDay && isSameTimeOfDay;
-  }
+  bool isSameDateTime(DateTime other) =>
+      isSameDay(other) && toTimeOfDay() == other.toTimeOfDay();
 
   bool isSameOrAfter(DateTime other) => isSameDateTime(other) || isAfter(other);
 }

lib/model/account_data.dart

@@ -196,15 +196,10 @@ class AccountData {
   /// Prefer this over embedding credentials in URLs — error logs and crash
   /// reports often capture the URL but not headers.
   String getBasicAuthHeader() {
-    if (!isPopulated()) {
-      throw Exception(
-        'AccountData (e.g. username or password) is not initialized!',
-      );
-    }
+    _requirePopulated();
     // Prefer the scoped app password once available; it survives real-password
     // rotation and is what the push-v2 registration is bound to.
-    final secret = _appPassword ?? _password;
-    return 'Basic ${base64Encode(utf8.encode('$_username:$secret'))}';
+    return _basicAuth(_appPassword ?? _password!);
   }
 
   /// Basic-auth header using the Talk app password — authenticates the
@@ -212,29 +207,32 @@ class AccountData {
   /// talk password has not been minted yet; callers treat that as a failed
   /// talk registration and retry on the next start.
   String getTalkBasicAuthHeader() {
-    if (!isPopulated()) {
-      throw Exception(
-        'AccountData (e.g. username or password) is not initialized!',
-      );
-    }
+    _requirePopulated();
     if (!hasAppPasswordTalk()) {
       throw StateError('Talk app password not available yet');
     }
-    return 'Basic ${base64Encode(utf8.encode('$_username:$_appPasswordTalk'))}';
+    return _basicAuth(_appPasswordTalk!);
   }
 
   /// Basic-auth header that always uses the real password. Needed exactly once,
   /// to mint the app password via `core/getapppassword` (an app password cannot
   /// mint another).
   String getRealPasswordBasicAuthHeader() {
+    _requirePopulated();
+    return _basicAuth(_password!);
+  }
+
+  void _requirePopulated() {
     if (!isPopulated()) {
       throw Exception(
         'AccountData (e.g. username or password) is not initialized!',
       );
     }
-    return 'Basic ${base64Encode(utf8.encode('$_username:$_password'))}';
   }
 
+  String _basicAuth(String secret) =>
+      'Basic ${base64Encode(utf8.encode('$_username:$secret'))}';
+
   /// Convenience wrapper around [getBasicAuthHeader] returning a single-entry
   /// header map ready to merge into HTTP request headers.
   Map<String, String> authHeaders() => {'Authorization': getBasicAuthHeader()};

lib/model/endpoint_data.dart

@@ -29,13 +29,10 @@ class EndpointData {
 
   EndpointData._construct();
 
-  EndpointMode getEndpointMode() {
-    late String existingName;
-    existingName = AccountData().getUsername();
-    return existingName.startsWith('google')
-        ? EndpointMode.stage
-        : EndpointMode.live;
-  }
+  EndpointMode getEndpointMode() =>
+      AccountData().getUsername().startsWith('google')
+      ? EndpointMode.stage
+      : EndpointMode.live;
 
   Endpoint nextcloud() => EndpointOptions(
     live: Endpoint(domain: 'cloud.marianum-fulda.de'),

lib/push/push_renderer.dart

@@ -371,13 +371,7 @@ class PushRenderer {
       jsonEncode({'chatToken': ?chatToken, 'nid': nid});
 
   /// Deterministic non-negative 31-bit id from a string, used when the push
-  /// carries no `nid`.
-  int _fallbackId(String? seed) {
-    if (seed == null || seed.isEmpty) return 0;
-    var hash = 0;
-    for (final unit in seed.codeUnits) {
-      hash = (hash * 31 + unit) & 0x7fffffff;
-    }
-    return hash;
-  }
+  /// carries no `nid`. Shares the hash with [stableChatNotificationId] (an
+  /// empty/null seed hashes to 0).
+  int _fallbackId(String? seed) => stableChatNotificationId(seed ?? '');
 }

lib/routing/app_routes.dart

@@ -440,7 +440,7 @@ class AppRoutes {
   static bool goToTab(BuildContext context, Modules module) {
     final index = AppModule.getBottomBarModules(
       context,
-    ).map((e) => e.module).toList().indexOf(module);
+    ).indexWhere((e) => e.module == module);
     if (index == -1) return false;
     Main.bottomNavigator.jumpToTab(index);
     return true;

lib/share_intent/pending_share.dart

@@ -1,3 +1,5 @@
+import 'package:flutter/foundation.dart';
+
 class PendingShare {
   final List<String> filePaths;
   final String? text;
@@ -17,12 +19,6 @@ class PendingShare {
   /// fires two `open(url)` requests per share (see ShareViewController), so
   /// the same share can arrive twice on the media stream — receivedAt is
   /// deliberately ignored here so such duplicates compare equal.
-  bool contentEquals(PendingShare other) {
-    if (text != other.text) return false;
-    if (filePaths.length != other.filePaths.length) return false;
-    for (var i = 0; i < filePaths.length; i++) {
-      if (filePaths[i] != other.filePaths[i]) return false;
-    }
-    return true;
-  }
+  bool contentEquals(PendingShare other) =>
+      text == other.text && listEquals(filePaths, other.filePaths);
 }

lib/state/app/infrastructure/utility_widgets/loadable_hydrated_bloc/loadable_hydrated_bloc.dart

@@ -123,23 +123,28 @@ abstract class LoadableHydratedBloc<
     fetch();
   }
 
+  /// Maps [e] through the shared error mapper and emits it as an [Error] event.
+  /// Does not guard [isClosed] — callers decide whether a late error still
+  /// applies.
+  void addLoadingError(Object e) => add(
+    Error(
+      LoadingError(
+        message: errorToUserMessage(e),
+        technicalDetails: errorToTechnicalDetails(e),
+        allowRetry: errorAllowsRetry(e),
+      ),
+    ),
+  );
+
   void fetch() {
     log('Fetching data for ${TState.toString()}');
     gatherData()
-        .catchError((e) {
+        .catchError((Object e) {
           log('Error while fetching ${TState.toString()}: ${e.toString()}');
           // The bloc may have been closed before this async error landed;
           // adding to a closed bloc throws, so swallow that case.
           if (isClosed) return;
-          add(
-            Error(
-              LoadingError(
-                message: errorToUserMessage(e),
-                technicalDetails: errorToTechnicalDetails(e),
-                allowRetry: errorAllowsRetry(e),
-              ),
-            ),
-          );
+          addLoadingError(e);
         })
         .then((value) {
           log('Fetch for ${TState.toString()} completed!');

lib/state/app/modules/chat/bloc/chat_bloc.dart

@@ -4,13 +4,11 @@ import 'dart:math' as math;
 
 import 'package:flutter/widgets.dart';
 
-import '../../../../../api/errors/error_mapper.dart';
 import '../../../../../api/marianumcloud/talk/chat/get_chat_response.dart';
 import '../../../../../api/marianumcloud/talk/chat/long_poll_chat.dart';
 import '../../../../../api/marianumcloud/talk/room/get_room_response.dart';
 import '../../../../../api/marianumcloud/talk/set_read_marker/set_read_marker.dart';
 import '../../../../../api/marianumcloud/talk/set_read_marker/set_read_marker_params.dart';
-import '../../../infrastructure/loadable_state/loading_error.dart';
 import '../../../infrastructure/utility_widgets/loadable_hydrated_bloc/loadable_hydrated_bloc.dart';
 import '../../../infrastructure/utility_widgets/loadable_hydrated_bloc/loadable_hydrated_bloc_event.dart';
 import '../../chat_list/bloc/chat_list_bloc.dart';
@@ -181,17 +179,7 @@ class ChatBloc
 
     if (!stillCurrent()) return;
 
-    if (capturedError != null) {
-      add(
-        Error(
-          LoadingError(
-            message: errorToUserMessage(capturedError),
-            technicalDetails: errorToTechnicalDetails(capturedError),
-            allowRetry: errorAllowsRetry(capturedError),
-          ),
-        ),
-      );
-    }
+    if (capturedError != null) addLoadingError(capturedError!);
   }
 
   void _startLongPoll(String token) {

lib/state/app/modules/chat_list/bloc/chat_list_bloc.dart

@@ -3,10 +3,8 @@ import 'dart:developer';
 
 import 'package:flutter_app_badge/flutter_app_badge.dart';
 
-import '../../../../../api/errors/error_mapper.dart';
 import '../../../../../api/marianumcloud/talk/chat/get_chat_response.dart';
 import '../../../../../api/marianumcloud/talk/room/get_room_response.dart';
-import '../../../infrastructure/loadable_state/loading_error.dart';
 import '../../../infrastructure/utility_widgets/loadable_hydrated_bloc/loadable_hydrated_bloc.dart';
 import '../../../infrastructure/utility_widgets/loadable_hydrated_bloc/loadable_hydrated_bloc_event.dart';
 import '../repository/chat_list_repository.dart';
@@ -87,17 +85,7 @@ class ChatListBloc
     } catch (e) {
       capturedError = e;
     }
-    if (capturedError != null) {
-      add(
-        Error(
-          LoadingError(
-            message: errorToUserMessage(capturedError),
-            technicalDetails: errorToTechnicalDetails(capturedError),
-            allowRetry: errorAllowsRetry(capturedError),
-          ),
-        ),
-      );
-    }
+    if (capturedError != null) addLoadingError(capturedError!);
   }
 
   /// Creates (or resolves) a 1:1 chat and returns its room token, or null in

lib/state/app/modules/files/bloc/files_bloc.dart

@@ -2,9 +2,7 @@ import 'dart:async';
 
 import 'package:collection/collection.dart';
 
-import '../../../../../api/errors/error_mapper.dart';
 import '../../../../../api/marianumcloud/webdav/queries/list_files/list_files_response.dart';
-import '../../../infrastructure/loadable_state/loading_error.dart';
 import '../../../infrastructure/utility_widgets/loadable_hydrated_bloc/loadable_hydrated_bloc.dart';
 import '../../../infrastructure/utility_widgets/loadable_hydrated_bloc/loadable_hydrated_bloc_event.dart';
 import '../repository/files_repository.dart';
@@ -112,16 +110,6 @@ class FilesBloc
       );
       add(DataGathered((s) => s.copyWith(listing: listing)));
     }
-    if (capturedError != null) {
-      add(
-        Error(
-          LoadingError(
-            message: errorToUserMessage(capturedError),
-            technicalDetails: errorToTechnicalDetails(capturedError),
-            allowRetry: errorAllowsRetry(capturedError),
-          ),
-        ),
-      );
-    }
+    if (capturedError != null) addLoadingError(capturedError!);
   }
 }

lib/state/app/modules/ticker/bloc/ticker_bloc.dart

@@ -1,5 +1,3 @@
-import '../../../../../api/marianumconnect/queries/get_ticker/get_ticker_response.dart';
-import '../../../../../api/marianumconnect/queries/get_ticker_nav/get_ticker_nav_response.dart';
 import '../../../infrastructure/utility_widgets/loadable_hydrated_bloc/loadable_hydrated_bloc.dart';
 import '../../../infrastructure/utility_widgets/loadable_hydrated_bloc/loadable_hydrated_bloc_event.dart';
 import '../repository/ticker_repository.dart';
@@ -10,9 +8,7 @@ class TickerBloc
     extends LoadableHydratedBloc<TickerEvent, TickerState, TickerRepository> {
   @override
   Future<void> gatherData() async {
-    final results = await Future.wait([repo.getTicker(), repo.getNav()]);
-    final ticker = results[0] as TickerResponse;
-    final nav = results[1] as TickerNavResponse;
+    final (ticker, nav) = await (repo.getTicker(), repo.getNav()).wait;
     add(DataGathered((state) => state.copyWith(ticker: ticker, nav: nav)));
   }
 

lib/view/pages/files/files_upload_dialog.dart

@@ -62,12 +62,14 @@ class _FilesUploadDialogState extends State<FilesUploadDialog> {
     );
   }
 
+  void _resetProgress() {
+    _isUploading = false;
+    _overallProgressValue = 0.0;
+    _infoText = '';
+  }
+
   void _showUploadError(String message) {
-    setState(() {
-      _isUploading = false;
-      _overallProgressValue = 0.0;
-      _infoText = '';
-    });
+    setState(_resetProgress);
     InfoDialog.show(
       context,
       message,
@@ -157,9 +159,7 @@ class _FilesUploadDialogState extends State<FilesUploadDialog> {
 
         if (replaceFiles != true) {
           setState(() {
-            _isUploading = false;
-            _overallProgressValue = 0.0;
-            _infoText = '';
+            _resetProgress();
             for (var element in conflictingFiles) {
               element.isConflicting = true;
             }
@@ -222,11 +222,7 @@ class _FilesUploadDialogState extends State<FilesUploadDialog> {
       }
 
       if (uploadTask.statusCode < 200 || uploadTask.statusCode > 299) {
-        setState(() {
-          _isUploading = false;
-          _overallProgressValue = 0.0;
-          _infoText = '';
-        });
+        setState(_resetProgress);
         if (!mounted) return;
         Navigator.of(context).pop();
         showHttpErrorCode(uploadTask.statusCode);
@@ -235,11 +231,7 @@ class _FilesUploadDialogState extends State<FilesUploadDialog> {
       }
     }
 
-    setState(() {
-      _isUploading = false;
-      _overallProgressValue = 0.0;
-      _infoText = '';
-    });
+    setState(_resetProgress);
     if (!mounted) return;
     Navigator.of(context).pop();
     widget.onUploadFinished(uploadetFilePaths);

lib/view/pages/grade_averages/grade_averages_view.dart

@@ -24,19 +24,12 @@ class GradeAveragesView extends StatelessWidget {
               Visibility(
                 visible: bloc.state.grades.isNotEmpty,
                 child: IconButton(
-                  onPressed: () {
-                    showDialog(
-                      context: context,
-                      builder: (context) => ConfirmDialog(
-                        title: 'Zurücksetzen?',
-                        content: 'Alle Einträge werden entfernt.',
-                        confirmButton: 'Zurücksetzen',
-                        onConfirm: () {
-                          bloc.add(ResetAll());
-                        },
-                      ),
-                    );
-                  },
+                  onPressed: () => ConfirmDialog(
+                    title: 'Zurücksetzen?',
+                    content: 'Alle Einträge werden entfernt.',
+                    confirmButton: 'Zurücksetzen',
+                    onConfirm: () => bloc.add(ResetAll()),
+                  ).asDialog(context),
                   icon: const Icon(Icons.delete_forever),
                 ),
               ),
@@ -64,17 +57,14 @@ class GradeAveragesView extends StatelessWidget {
                     .toList(),
                 onSelected: (isMiddleSchool) {
                   if (bloc.state.grades.isNotEmpty) {
-                    showDialog(
-                      context: context,
-                      builder: (context) => ConfirmDialog(
-                        title: 'Notensystem wechseln',
-                        content:
-                            'Beim Wechsel des Notensystems werden alle Einträge zurückgesetzt.',
-                        confirmButton: 'Fortfahren',
-                        onConfirm: () =>
-                            bloc.add(GradingSystemChanged(isMiddleSchool)),
-                      ),
-                    );
+                    ConfirmDialog(
+                      title: 'Notensystem wechseln',
+                      content:
+                          'Beim Wechsel des Notensystems werden alle Einträge zurückgesetzt.',
+                      confirmButton: 'Fortfahren',
+                      onConfirm: () =>
+                          bloc.add(GradingSystemChanged(isMiddleSchool)),
+                    ).asDialog(context);
                   } else {
                     bloc.add(GradingSystemChanged(isMiddleSchool));
                   }

lib/view/pages/marianum_dates/marianum_dates_view.dart

@@ -27,7 +27,7 @@ class MarianumDatesView extends StatelessWidget {
     return keys.map((key) {
       final first = byMonth[key]!.first.start;
       final label = first.formatMonthYear().toUpperCase();
-      return _MonthGroup(key: key, label: label, events: byMonth[key]!);
+      return _MonthGroup(label: label, events: byMonth[key]!);
     }).toList();
   }
 
@@ -117,8 +117,7 @@ class MarianumDatesView extends StatelessWidget {
 }
 
 class _MonthGroup {
-  final String key;
   final String label;
   final List<MarianumDate> events;
-  _MonthGroup({required this.key, required this.label, required this.events});
+  _MonthGroup({required this.label, required this.events});
 }

lib/view/pages/marianum_message/marianum_message_list_view.dart

@@ -6,6 +6,7 @@ import '../../../state/app/infrastructure/loadable_state/view/loadable_state_con
 import '../../../state/app/infrastructure/utility_widgets/bloc_module.dart';
 import '../../../state/app/modules/marianum_message/bloc/marianum_message_bloc.dart';
 import '../../../state/app/modules/marianum_message/bloc/marianum_message_state.dart';
+import '../../../widget/centered_leading.dart';
 import 'search_marianum_messages.dart';
 
 class MarianumMessageListView extends StatelessWidget {
@@ -40,12 +41,9 @@ class MarianumMessageListView extends StatelessWidget {
         child: (state, loading) => ListView.builder(
           itemCount: state.messageList.messages.length,
           itemBuilder: (context, index) {
-            var message = state.messageList.messages.toList()[index];
+            var message = state.messageList.messages[index];
             return ListTile(
-              leading: const Column(
-                mainAxisAlignment: MainAxisAlignment.center,
-                children: [Icon(Icons.newspaper)],
-              ),
+              leading: const CenteredLeading(Icon(Icons.newspaper)),
               title: Text(message.name, overflow: TextOverflow.ellipsis),
               subtitle: Column(
                 crossAxisAlignment: CrossAxisAlignment.start,

lib/view/pages/marianum_message/marianum_message_view.dart

@@ -2,7 +2,6 @@ import 'dart:typed_data';
 
 import 'package:flutter/material.dart';
 import 'package:syncfusion_flutter_pdfviewer/pdfviewer.dart';
-import 'package:url_launcher/url_launcher.dart';
 
 import '../../../api/marianumconnect/queries/get_newsletter_file/get_newsletter_file.dart';
 import '../../../widget/app_progress_indicator.dart';
@@ -39,20 +38,8 @@ class _MessageViewState extends State<MessageView> {
         return SfPdfViewer.memory(
           snapshot.data!,
           enableHyperlinkNavigation: true,
-          onHyperlinkClicked: (PdfHyperlinkClickedDetails e) {
-            showDialog(
-              context: context,
-              builder: (context) => ConfirmDialog(
-                title: 'Link öffnen',
-                content: 'Möchtest du den folgenden Link öffnen?\n${e.uri}',
-                confirmButton: 'Öffnen',
-                onConfirm: () => launchUrl(
-                  Uri.parse(e.uri),
-                  mode: LaunchMode.externalApplication,
-                ),
-              ),
-            );
-          },
+          onHyperlinkClicked: (PdfHyperlinkClickedDetails e) =>
+              ConfirmDialog.openBrowser(context, e.uri),
         );
       },
     ),

lib/view/pages/marianum_message/search_marianum_messages.dart

@@ -2,6 +2,7 @@ import 'package:flutter/material.dart';
 
 import '../../../routing/app_routes.dart';
 import '../../../state/app/modules/marianum_message/bloc/marianum_message_state.dart';
+import '../../../widget/centered_leading.dart';
 import '../../../widget/placeholder_view.dart';
 
 class SearchMarianumMessages extends SearchDelegate<MarianumMessage?> {
@@ -45,10 +46,7 @@ class SearchMarianumMessages extends SearchDelegate<MarianumMessage?> {
       itemBuilder: (_, i) {
         final message = matches[i];
         return ListTile(
-          leading: const Column(
-            mainAxisAlignment: MainAxisAlignment.center,
-            children: [Icon(Icons.newspaper)],
-          ),
+          leading: const CenteredLeading(Icon(Icons.newspaper)),
           title: Text(message.name, overflow: TextOverflow.ellipsis),
           subtitle: Text('vom ${message.date}'),
           trailing: const Icon(Icons.arrow_right),

lib/view/pages/settings/sections/about_section.dart

@@ -1,7 +1,6 @@
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
-import 'package:jiffy/jiffy.dart';
 import 'package:package_info_plus/package_info_plus.dart';
 
 import '../../../../state/app/modules/settings/bloc/settings_cubit.dart';
@@ -71,7 +70,7 @@ class AboutSection extends StatelessWidget {
       applicationLegalese:
           'Alles für deinen Schulalltag am Marianum Fulda.\n\n'
           "${kReleaseMode ? "Production" : "Development ${kProfileMode ? "(Profiling)" : "(Debug)"}"} build.\n\n"
-          'Marianum Fulda\n2019-2020 & 2022-${Jiffy.now().year}\nElias Müller',
+          'Marianum Fulda\n2019-2020 & 2022-${DateTime.now().year}\nElias Müller',
     );
   }
 

lib/view/pages/share_intent/share_chat_picker.dart

@@ -166,13 +166,24 @@ Future<void> _afterExternalFilesUploaded(
   GetRoomResponseObject room,
   List<String> uploadedRemotePaths,
   PendingShare share,
-) async {
+) => _runShareFlow(
+  context,
+  action: () =>
+      shareFilesToChat(token: room.token, remoteFilePaths: uploadedRemotePaths),
+  onSuccess: () => _setExternalDraftAndOpenChat(context, room, share),
+);
+
+/// Shared share-flow scaffolding: shows the blocking spinner, runs [action],
+/// maps failures to an error dialog (popping the spinner first), and invokes
+/// [onSuccess] on success while still mounted.
+Future<void> _runShareFlow(
+  BuildContext context, {
+  required Future<void> Function() action,
+  required VoidCallback onSuccess,
+}) async {
   unawaited(_showBlockingSpinner(context));
   try {
-    await shareFilesToChat(
-      token: room.token,
-      remoteFilePaths: uploadedRemotePaths,
-    );
+    await action();
   } catch (e) {
     if (context.mounted) Navigator.of(context).pop();
     if (context.mounted) {
@@ -186,7 +197,7 @@ Future<void> _afterExternalFilesUploaded(
     return;
   }
   if (!context.mounted) return;
-  _setExternalDraftAndOpenChat(context, room, share);
+  onSuccess();
 }
 
 void _setExternalDraftAndOpenChat(
@@ -213,61 +224,30 @@ Future<void> _internalShareFlow(
   BuildContext context,
   GetRoomResponseObject room,
   RemoteFileRef file,
-) async {
-  unawaited(_showBlockingSpinner(context));
-  try {
-    await shareFilesToChat(
-      token: room.token,
-      remoteFilePaths: [file.path],
-    );
-  } catch (e) {
-    if (context.mounted) Navigator.of(context).pop();
-    if (context.mounted) {
-      InfoDialog.show(
-        context,
-        errorToUserMessage(e),
-        title: 'Fehler',
-        copyable: true,
-      );
-    }
-    return;
-  }
-  if (!context.mounted) return;
-  _finishWithChat(context, room);
-}
+) => _runShareFlow(
+  context,
+  action: () =>
+      shareFilesToChat(token: room.token, remoteFilePaths: [file.path]),
+  onSuccess: () => _finishWithChat(context, room),
+);
 
 Future<void> _forwardMessageFlow(
   BuildContext context,
   GetRoomResponseObject room,
   String? text,
   RemoteFileRef? file,
-) async {
-  unawaited(_showBlockingSpinner(context));
-  try {
+) => _runShareFlow(
+  context,
+  action: () async {
     if (file != null) {
-      await shareFilesToChat(
-        token: room.token,
-        remoteFilePaths: [file.path],
-      );
+      await shareFilesToChat(token: room.token, remoteFilePaths: [file.path]);
     }
     if (text != null && text.isNotEmpty) {
       await SendMessage(room.token, SendMessageParams(text)).run();
     }
-  } catch (e) {
-    if (context.mounted) Navigator.of(context).pop();
-    if (context.mounted) {
-      InfoDialog.show(
-        context,
-        errorToUserMessage(e),
-        title: 'Fehler',
-        copyable: true,
-      );
-    }
-    return;
-  }
-  if (!context.mounted) return;
-  _finishWithChat(context, room);
-}
+  },
+  onSuccess: () => _finishWithChat(context, room),
+);
 
 /// Modal progress overlay shown during share-API roundtrips. The dialog is
 /// popped together with the picker by the subsequent popUntil(isFirst).

lib/view/pages/share_intent/share_target_page.dart

@@ -121,26 +121,15 @@ class ShareTargetPage extends StatelessWidget {
 
   Widget _buildFilePreview(BuildContext context) {
     if (share.filePaths.length == 1) {
-      final path = share.filePaths.first;
-      final name = path.split(Platform.pathSeparator).last;
       return ConstrainedBox(
         constraints: const BoxConstraints(maxHeight: 320),
-        child: Container(
-          decoration: BoxDecoration(
-            color: Theme.of(context).colorScheme.surfaceContainer,
-            borderRadius: BorderRadius.circular(12),
-          ),
-          clipBehavior: Clip.antiAlias,
-          child: _isImagePath(path)
-              ? Image.file(
-                  File(path),
-                  fit: BoxFit.contain,
-                  // Decode at most ~1080px so 50-MP gallery photos don't
-                  // balloon the decode buffer just to render at <320px high.
-                  cacheWidth: 1080,
-                  errorBuilder: (_, _, _) => _fileFallbackLarge(name),
-                )
-              : _fileFallbackLarge(name),
+        // Decode at most ~1080px so 50-MP gallery photos don't balloon the
+        // decode buffer just to render at <320px high.
+        child: _filePreviewTile(
+          context,
+          share.filePaths.first,
+          fit: BoxFit.contain,
+          cacheWidth: 1080,
         ),
       );
     }
@@ -153,28 +142,38 @@ class ShareTargetPage extends StatelessWidget {
         mainAxisSpacing: 10,
       ),
       itemCount: share.filePaths.length,
-      itemBuilder: (context, i) {
-        final path = share.filePaths[i];
-        final name = path.split(Platform.pathSeparator).last;
-        return Container(
-          decoration: BoxDecoration(
-            color: Theme.of(context).colorScheme.surfaceContainer,
-            borderRadius: BorderRadius.circular(12),
-          ),
-          clipBehavior: Clip.antiAlias,
-          child: _isImagePath(path)
-              ? Image.file(
-                  File(path),
-                  fit: BoxFit.cover,
-                  // Grid tiles are ~half-screen wide; 480px decode is
-                  // sharp on 3x displays without blowing up memory when
-                  // many files are shared at once.
-                  cacheWidth: 480,
-                  errorBuilder: (_, _, _) => _fileFallbackLarge(name),
-                )
-              : _fileFallbackLarge(name),
-        );
-      },
+      // Grid tiles are ~half-screen wide; 480px decode is sharp on 3x displays
+      // without blowing up memory when many files are shared at once.
+      itemBuilder: (context, i) => _filePreviewTile(
+        context,
+        share.filePaths[i],
+        fit: BoxFit.cover,
+        cacheWidth: 480,
+      ),
+    );
+  }
+
+  Widget _filePreviewTile(
+    BuildContext context,
+    String path, {
+    required BoxFit fit,
+    required int cacheWidth,
+  }) {
+    final name = path.split(Platform.pathSeparator).last;
+    return Container(
+      decoration: BoxDecoration(
+        color: Theme.of(context).colorScheme.surfaceContainer,
+        borderRadius: BorderRadius.circular(12),
+      ),
+      clipBehavior: Clip.antiAlias,
+      child: _isImagePath(path)
+          ? Image.file(
+              File(path),
+              fit: fit,
+              cacheWidth: cacheWidth,
+              errorBuilder: (_, _, _) => _fileFallbackLarge(name),
+            )
+          : _fileFallbackLarge(name),
     );
   }
 

lib/view/pages/talk/chat_view.dart

@@ -110,10 +110,7 @@ class _ChatViewState extends State<ChatView> with RouteAware {
     if (state.currentToken != widget.room.token) return;
     final response = state.chatResponse;
     if (response == null) return;
-    var maxId = 0;
-    for (final m in response.data) {
-      if (m.id > maxId) maxId = m.id;
-    }
+    final maxId = response.data.map((m) => m.id).fold<int>(0, math.max);
     if (maxId == 0) return;
     _chatListBlocRef?.markRoomAsRead(widget.room.token, maxId);
     unawaited(_chatBlocRef!.sendServerReadMarker(widget.room.token, maxId));
@@ -230,21 +227,20 @@ class _ChatViewState extends State<ChatView> with RouteAware {
         ? _searchQuery
         : null;
 
+    final commonRead = int.parse(
+      response.headers?['x-chat-last-common-read'] ?? '0',
+    );
+
     final messages = <Widget>[];
     final chronologicalMatchIndex = <int, int>{};
     var lastDate = DateTime.now();
     for (final element in response.sortByTimestamp()) {
+      if (ChatSearchController.isHiddenSystemMessage(element)) continue;
+
       final elementDate = DateTime.fromMillisecondsSinceEpoch(
         element.timestamp * 1000,
       );
 
-      if (element.systemMessage.contains('reaction')) continue;
-      if (element.systemMessage.contains('poll_voted')) continue;
-      if (element.systemMessage.contains('message_deleted')) continue;
-      final commonRead = int.parse(
-        response.headers?['x-chat-last-common-read'] ?? '0',
-      );
-
       if (!elementDate.isSameDay(lastDate)) {
         lastDate = elementDate;
         messages.add(

lib/view/pages/talk/data/chat_bubble_styles.dart

@@ -4,18 +4,6 @@ import '../../../../theming/app_theme.dart';
 import '../widgets/bubble.dart';
 
 extension ColorExtensions on Color {
-  Color invert() {
-    final invertedR = 1.0 - r;
-    final invertedG = 1.0 - g;
-    final invertedB = 1.0 - b;
-    return Color.from(
-      alpha: a,
-      red: invertedR,
-      green: invertedG,
-      blue: invertedB,
-    );
-  }
-
   Color withWhite(int whiteValue) {
     final value = whiteValue / 255.0;
     return Color.from(alpha: a, red: value, green: value, blue: value);

lib/view/pages/talk/data/chat_message.dart

@@ -16,8 +16,6 @@ class ChatMessage {
   RichObjectString? file;
   String content = '';
 
-  bool get containsFile => file != null;
-
   ChatMessage({required this.originalMessage, this.originalData}) {
     if (originalData?.containsKey('file') ?? false) {
       file = originalData?['file'];

lib/view/pages/talk/data/chat_search_controller.dart

@@ -10,6 +10,14 @@ class ChatSearchMatch {
 }
 
 class ChatSearchController {
+  /// System messages that are folded into other bubbles (reactions, poll
+  /// votes, deletions) and therefore never rendered nor searched as their own
+  /// entry.
+  static bool isHiddenSystemMessage(GetChatResponseObject element) =>
+      element.systemMessage.contains('reaction') ||
+      element.systemMessage.contains('poll_voted') ||
+      element.systemMessage.contains('message_deleted');
+
   static List<ChatSearchMatch> findMatches(
     GetChatResponse response,
     String query,
@@ -19,9 +27,7 @@ class ChatSearchController {
 
     final matches = <ChatSearchMatch>[];
     for (final element in response.sortByTimestamp()) {
-      if (element.systemMessage.contains('reaction')) continue;
-      if (element.systemMessage.contains('poll_voted')) continue;
-      if (element.systemMessage.contains('message_deleted')) continue;
+      if (isHiddenSystemMessage(element)) continue;
 
       final haystackText = RichObjectStringProcessor.parseToString(
         element.message,

lib/view/pages/talk/widgets/answer_reference.dart

@@ -17,28 +17,17 @@ class AnswerReference extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    var style = ChatBubbleStyles(context);
+    final style = ChatBubbleStyles(context);
+    final isSelf = referenceMessage.actorId == selfId;
+    final accent = isSelf
+        ? style.getSelfStyle(false).color!.withGreen(200)
+        : style.getRemoteStyle(false).color!.withWhite(200);
     return DecoratedBox(
       decoration: BoxDecoration(
-        color: referenceMessage.actorId == selfId
-            ? style
-                  .getSelfStyle(false)
-                  .color!
-                  .withGreen(200)
-                  .withValues(alpha: 0.2)
-            : style
-                  .getRemoteStyle(false)
-                  .color!
-                  .withWhite(200)
-                  .withValues(alpha: 0.2),
+        color: accent.withValues(alpha: 0.2),
         borderRadius: const BorderRadius.all(Radius.circular(5)),
         border: Border(
-          left: BorderSide(
-            color: referenceMessage.actorId == selfId
-                ? style.getSelfStyle(false).color!.withGreen(200)
-                : style.getRemoteStyle(false).color!.withWhite(200),
-            width: 5,
-          ),
+          left: BorderSide(color: accent, width: 5),
         ),
       ),
       child: Padding(
@@ -51,9 +40,7 @@ class AnswerReference extends StatelessWidget {
               maxLines: 1,
               style: TextStyle(
                 overflow: TextOverflow.ellipsis,
-                color: referenceMessage.actorId == selfId
-                    ? style.getSelfStyle(false).color!.withGreen(200)
-                    : style.getRemoteStyle(false).color!.withWhite(200),
+                color: accent,
                 fontSize: 12,
               ),
             ),

lib/view/pages/timetable/data/timetable_appointment_factory.dart

@@ -8,6 +8,7 @@ import '../../../../api/mhsl/custom_timetable_event/custom_timetable_event.dart'
 import '../../../../storage/timetable_settings.dart';
 import 'arbitrary_appointment.dart';
 import 'lesson_color.dart';
+import 'lesson_merger.dart';
 import 'lesson_status.dart';
 import 'lesson_type_label.dart';
 import 'rrule_with_exceptions.dart';
@@ -33,7 +34,7 @@ class TimetableAppointmentFactory {
 
   List<Appointment> build() {
     final source = settings.connectDoubleLessons
-        ? _mergeAdjacentLessons(lessons)
+        ? LessonMerger.merge(lessons)
         : lessons;
     return [
       ...source.map(_lessonToAppointment),
@@ -267,68 +268,4 @@ class TimetableAppointmentFactory {
         .trim();
     return cleaned.isEmpty ? null : cleaned;
   }
-
-  // Pure: builds a new list, does not mutate inputs. The previous version
-  // mutated `previous.endTime` in place which caused merged blocks to grow
-  // further on subsequent rebuilds when the same lesson objects were observed
-  // again by the next merge pass.
-  static List<McTimetableEntry> _mergeAdjacentLessons(
-    List<McTimetableEntry> input, {
-    Duration maxGap = const Duration(minutes: 5),
-  }) {
-    if (input.isEmpty) return const [];
-
-    final sorted = [...input]
-      ..sort((a, b) => a.startDateTime.compareTo(b.startDateTime));
-
-    final merged = <McTimetableEntry>[];
-    for (final current in sorted) {
-      if (merged.isNotEmpty && _canMerge(merged.last, current, maxGap)) {
-        final prev = merged.removeLast();
-        merged.add(_extendedEnd(prev, current.endTime));
-      } else {
-        merged.add(current);
-      }
-    }
-    return merged;
-  }
-
-  static McTimetableEntry _extendedEnd(
-    McTimetableEntry source,
-    DateTime newEndTime,
-  ) => McTimetableEntry(
-    id: source.id,
-    date: source.date,
-    startTime: source.startTime,
-    endTime: newEndTime,
-    subjects: source.subjects,
-    teachers: source.teachers,
-    rooms: source.rooms,
-    classNames: source.classNames,
-    lessonType: source.lessonType,
-    status: source.status,
-    substitutionText: source.substitutionText,
-    lessonText: source.lessonText,
-    infoText: source.infoText,
-  );
-
-  static bool _canMerge(
-    McTimetableEntry a,
-    McTimetableEntry b,
-    Duration maxGap,
-  ) {
-    if (a.subjects.firstOrNull != b.subjects.firstOrNull) return false;
-    if (a.rooms.firstOrNull != b.rooms.firstOrNull) return false;
-    if (a.teachers.firstOrNull?.shortName !=
-        b.teachers.firstOrNull?.shortName) {
-      return false;
-    }
-    if (a.status != b.status) return false;
-
-    // Merge only sequential lessons (b starts at or after a ends, within the
-    // tolerance). Without the lower bound, identical-metadata lessons that
-    // overlap in time would silently collapse into one.
-    final gap = b.startDateTime.difference(a.endDateTime);
-    return !gap.isNegative && gap <= maxGap;
-  }
 }

lib/view/pages/timetable/details/lesson_sheet.dart

@@ -268,12 +268,10 @@ class LessonSheet {
     );
   }
 
-  static String _line(String name, {String? longname, String? extra}) {
+  static String _line(String name, {String? longname}) {
     final parts = <String>[if (name.isNotEmpty) name else '?'];
     final ln = (longname ?? '').trim();
     if (ln.isNotEmpty && ln != name) parts.add('($ln)');
-    final ex = (extra ?? '').trim();
-    if (ex.isNotEmpty) parts.add('· $ex');
     return parts.join(' ');
   }
 

lib/view/pages/timetable/widgets/calendar/outside_chips.dart

@@ -116,12 +116,9 @@ class _OutsideDayColumn extends StatelessWidget {
 
   static String _subtitleFor(Appointment a) {
     if (isAllDayLike(a)) return 'Ganztägig';
-    return '${_hm(a.startTime)}–${_hm(a.endTime)}';
+    return '${a.startTime.formatHm()}–${a.endTime.formatHm()}';
   }
 
-  static String _hm(DateTime t) =>
-      '${t.hour.toString().padLeft(2, '0')}:${t.minute.toString().padLeft(2, '0')}';
-
   @override
   Widget build(BuildContext context) {
     if (appointments.isEmpty) return const SizedBox.shrink();
@@ -182,9 +179,7 @@ class _OutsideChip extends StatelessWidget {
   Widget build(BuildContext context) {
     final theme = Theme.of(context);
     final allDay = isAllDayLike(appointment);
-    final timeLabel = allDay
-        ? null
-        : '${appointment.startTime.hour.toString().padLeft(2, '0')}:${appointment.startTime.minute.toString().padLeft(2, '0')}';
+    final timeLabel = allDay ? null : appointment.startTime.formatHm();
 
     // Past chips fade further, future/ongoing ones get a more saturated tint
     // so the strip no longer reads as one uniform grey block.

lib/view/pages/timetable/widgets/calendar/week_grid.dart

@@ -289,14 +289,11 @@ class _DayColumn extends StatelessWidget {
   }
 
   static String _overflowSubtitle(Appointment apt) {
-    final time = '${_formatHm(apt.startTime)}–${_formatHm(apt.endTime)}';
+    final time = '${apt.startTime.formatHm()}–${apt.endTime.formatHm()}';
     final loc = apt.location?.replaceAll('\n', ' · ');
     return loc != null && loc.isNotEmpty ? '$time · $loc' : time;
   }
 
-  static String _formatHm(DateTime t) =>
-      '${t.hour.toString().padLeft(2, '0')}:${t.minute.toString().padLeft(2, '0')}';
-
   @override
   Widget build(BuildContext context) {
     final theme = Theme.of(context);

lib/widget/async_actions/async_action_controller.dart

@@ -3,6 +3,11 @@ part of '../async_action_button.dart';
 typedef AsyncActionCallback = Future<void> Function();
 typedef AsyncErrorBuilder = String Function(Object error);
 
+/// Shared style for the inline error message the async-button family renders
+/// beneath a control after a caught failure.
+TextStyle _asyncErrorTextStyle(BuildContext context) =>
+    TextStyle(color: Theme.of(context).colorScheme.error, fontSize: 13);
+
 /// Wraps [action] with a try/catch that pops up an [InfoDialog] on failure
 /// (using [errorBuilder] or the default error mapper). Returns `true` on
 /// success, `false` on caught failure.

lib/widget/async_actions/async_dialog_action.dart

@@ -44,10 +44,7 @@ class _AsyncDialogActionState extends State<AsyncDialogAction> {
               child: Text(
                 err,
                 textAlign: TextAlign.center,
-                style: TextStyle(
-                  color: Theme.of(context).colorScheme.error,
-                  fontSize: 13,
-                ),
+                style: _asyncErrorTextStyle(context),
               ),
             ),
           Row(

lib/widget/async_actions/async_list_tile.dart

@@ -76,13 +76,7 @@ class _AsyncListTileState extends State<AsyncListTile> {
           if (err != null)
             Padding(
               padding: const EdgeInsets.only(left: 16, right: 16, bottom: 8),
-              child: Text(
-                err,
-                style: TextStyle(
-                  color: Theme.of(context).colorScheme.error,
-                  fontSize: 13,
-                ),
-              ),
+              child: Text(err, style: _asyncErrorTextStyle(context)),
             ),
         ],
       );

lib/widget/async_actions/async_mixin.dart

@@ -108,10 +108,7 @@ class _InlineErrorWrapper extends StatelessWidget {
               Text(
                 err,
                 textAlign: TextAlign.center,
-                style: TextStyle(
-                  color: Theme.of(context).colorScheme.error,
-                  fontSize: 13,
-                ),
+                style: _asyncErrorTextStyle(context),
               ),
             ],
           ],

lib/widget/debug/cache_view.dart

@@ -1,4 +1,3 @@
-import 'dart:async';
 import 'dart:convert';
 import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
@@ -85,11 +84,3 @@ class _CacheViewState extends State<CacheView> {
     ),
   );
 }
-
-extension FutureExtension<T> on Future<T> {
-  bool isCompleted() {
-    final completer = Completer<T>();
-    then(completer.complete).catchError(completer.completeError);
-    return completer.isCompleted;
-  }
-}

lib/widget/file_pick.dart

@@ -17,7 +17,6 @@ class FilePick {
 
   static Future<List<String>?> documentPick() async {
     final result = await FilePicker.pickFiles(allowMultiple: true);
-    final paths = result?.files.nonNulls.map((e) => e.path).toList();
-    return paths?.nonNulls.toList();
+    return result?.files.map((e) => e.path).nonNulls.toList();
   }
 }

lib/widget_data/widget_sync.dart

@@ -39,21 +39,15 @@ class WidgetSync {
     _initialised = true;
   }
 
-  static Future<void> writeDayData(WidgetTimetableData data) async {
-    await ensureInitialized();
-    await HomeWidget.saveWidgetData<String>(dayDataKey, jsonEncode(data.toJson()));
-    await HomeWidget.saveWidgetData<String>(
-      fetchedAtKey,
-      data.fetchedAt.toIso8601String(),
-    );
-  }
+  static Future<void> writeDayData(WidgetTimetableData data) =>
+      _writeData(dayDataKey, data);
 
-  static Future<void> writeWeekData(WidgetTimetableData data) async {
+  static Future<void> writeWeekData(WidgetTimetableData data) =>
+      _writeData(weekDataKey, data);
+
+  static Future<void> _writeData(String key, WidgetTimetableData data) async {
     await ensureInitialized();
-    await HomeWidget.saveWidgetData<String>(
-      weekDataKey,
-      jsonEncode(data.toJson()),
-    );
+    await HomeWidget.saveWidgetData<String>(key, jsonEncode(data.toJson()));
     await HomeWidget.saveWidgetData<String>(
       fetchedAtKey,
       data.fetchedAt.toIso8601String(),